James b



J. B. ALLFREE.

Pate nted Oct. 8, 1889.

No. 412,693. I

uililliun "Mimi" E Wm i UNITED STATES PATENT OFFICE.

ticularly described or pointed out,

.valve more sensitiveand more completely JAMES B. ALLFREE, orINDIANAPOLIS, INDIANA.

BALANCED SLIDE-VALVE.

SPEOIFIGATIO N forming part of Letters Patent No. 412,693, dated October8, 1889.

Application filed April 3, 1889. Serial No. 305,844- (NomodeL) To allwhom it may concern:

Be it known that 1, JAMES B. ALLFREE, a citizen of the United States,residing at Indianapolis, in the county of Marion and State of Indiana,have invented certain new and useful Improvements in Balanced SlideValves; and I do hereby declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

This invention relates to certain new and useful improvements inbalanced slide-valves; and it consists, substantially, in such featuresof arrangement, construction, and combinations of parts as willhereinafter be more par- The invention is intended as an improvementupon the balanced slide-valve for which Letters Patent No. 280,993 weregranted me on the 10th day of July, 1883; and it has for its object torender the valve adjustable, so that its contact with its-valve-seat maybe easily regulated; to make the operation of the under control, beingadjustable While the engine is in operation, and to permit of construction' with greater accuracy and less cost, all as will more fullyhereinafter appear, when taken in connection with the accompanyingdrawings, wherein Figure 1 represents a longitudinal side elevation ofmy improved balanced slide-valve, the same being partly in section tomore clearly indicate the construction of parts. Fig. 2 is a transversesectional view of the valve, together with the steam-chest in which thesame slides. Fig. 3 is a view in detail representing the connectionresorted to between the eccentric-rod of the engine and the valve-stem.I

, In the former patent referred to the two valves are held apart bysprings, and the distance they can move apart is determined by a clampat either end. These clamps are formed with ledges havingrectangularsides, which receive ledges or lugs on the ends of the valves, alsorectangular, forming stops for the valves, and their construction issuch that the extent of their movement apart cannot be adjusted orregulated. To enable the valves to do their work properly, these clampsmust be neatly fitted by a skilled mechanic, 4

and there is no provision except by refitting, to take up any wear or tocorrect a bad fit In the present invention springs are employed in likemanner tohold the valves apart; but the ledges. on the clamps havebeveled or inclined sides, and the lugs on the ends of the valve whichare received by said clamps are also beveled correspondingly, so that ifthe clamps are moved toward or from each otherthe distance the valvescan move apart is increased or decreased in proportion to the distancethe clamps are moved. The movement of the clamps necessary to adjust thevalves is effected by rotating the valve-stem, which passeslongitudinally between the valves, and may be squared at any partoutside of the steam-chest, and which is provided with a right-handedscrew at one end of the valves and a left-handed screw at the other end,which take into screw-threaded holes in the clamps provided for thatpurpose.

The valve-stem imparts reciprocal motion to the valves, and in order toprevent any i change of position of the clamps by this reciprocalmotion, and also to insure the same regulation of either clamp when thevalvestem is rotated, it is necessary to adapt the valve-stem to thevalves in such a way as to permit its rotation. and to prevent itslongitudinal motion with respect to the valves themselves, while thelatter are held firmly on the stem and are free to move transversely (toor from the valve-seats) by the action of the steam and springs. This-iseffected by placing on the valve-stem inside, between the valves,lock-nuts and washers, which are faced off and bear against facedofiportions of the valves squared and faced to receive them, and in thisway also isprovision made to receive the thrust by which the valves areactuated. The spaces on the valve-stem where these nuts are located maybe flattened or the threads removed on one or two sides of the stem. andthe hole through the washer shaped to fit neatly thereon, for thepurpose of preventing the washer from turning on the stem and looseningthe nuts when said. stem is rotated.

the letters marked thereon, A represents the valves,- two in number,counterparts of each other, and each one seated before the ports in thesteam-chest A. The said valves are maintained apart from each other bythe steam-pressure when the engine is in operation and by means of thesprings B, by the action of which they are free to move transversely orto and from the valve-seats, and to they are provided, as usual, withsteam-ports.

(Designated by the letter C.)

The valves are provided with lugs a on their ends, the sides of whichare beveled, as shown, and these lugs enter or are received I 5 underthe ledges 1), formed on the adj ustingclamps D, and also havingcorrespondinglybeveled sides. From this construction the distance thevalves can move apart may be increased or decreased by simply turningthe valve-stem E, which passes longitudinally between the valves, andwhich is provided at one end with a right-handed screw and at the otherend with a lefthanded screw, which take into screw-threaded holes in theclamps, as shown, said clamps being lined with brass or other suitablematerial to prevent sticking from oxidization.

Located on the valve-stem, inside and between the valves, are washers LL and lock- 0 nuts M M, which, as before stated, serve to receive thethrust required to actuate the valves as they are reciprocated beforethe valve-seats by the stem,by virtue of their being squared and facedoff and bearing against 5 faced-01f portions of the valves. The saidnuts and washers prevent any change of position of the clamps apt tooccur on the reciprocation of the valve-stem, as well as anylongitudinal motion of said stem with respect to the valves when thesame is rotated to move the clamps in or out.

By reference to Fig. 3 of the drawings the manner of connection betweenthe valve-stem and the eccentric-rod will be seen. This c011- nection isconstituted of a yoke R, to which the eccentric-rod S is connected, andwhich yoke is held by brackets s s, bolted to the engine-bed, as shown.The yoke has a projection t, through which thevalve-stem passes,

and a set-screw is provided to tighten against the stem, as shown. Theend of the valvestem is screw-threaded, as explained and shown, andfitting thereon on either side of the projection 15 are the nuts T T andU,

which firmly hold said stem. Then it is desired to rotate thevalve-stem, the nut U is loosened. The stem is then free to rotatewithout changing position longitudinally, as the two nuts T T are lockedagainst each other, forming a collar. When it is desired to move thevalve-stem longitudinally, then all the nuts are loosened and set asdesired. The point of the valve-stem is made square, for the purpose offitting a wrench with which to rotate the stem and also hold it inposition while the nut U is being firmly set. The accidental turning ofthe valve-stem is of course prevented when the nutU is screwed tightagainst the nuts T T.

From the foregoing it will be seen that by the construction andarrangement of the several parts a uniform wear is had, as well asreliable action, and that the valves may be easily adjusted to suitvarying requirements incident to their use and operation.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. In balanced slide-valves, the combination, with the valve-stem, ofthe two valvesSo adapted to move to and from each other and provided ontheir ends with lugs or ledges having beveled sides, and two clampscorrespondingly formed and adjustable on the stem, substantially asdescribed.

2. In balanced slide-valves, the combination, with the valve-stemprovided at one end with a right-handed screw and at the other end witha left-handed screw, of two valves held apart by springs and provided ontheir ends with lugs having beveled sides and two clamps screw-threadedto fit the ends of the valve-stem and formed with ledges fitting saidlugs, substantially as described.

3. The combination, with the valve-stem, 5 the two valves adapted tomove transversely with respect thereto, and means for increasing ordecreasing the extent of such movement, of locknuts and washers placedon the valve-stem inside between the valves, .the same being faced offand bearing against faced-oif portions of the valves, which are squaredand faced to receive them, substantially as described.

4. The combination, with the valve-stem, of two valves adapted to movetransversely with respect thereto and form ed on their ends with thelugs or ledges having beveled sides, the two clamps correspondinglyformed for adjustin g the valves, and lock-n uts and washers placed onthe valve-stem inside between the valves, the same being faced off andbearing against faced-off portions of the valves, which are squared andfaced to receive them, substantially as described.

5. In balanced slide-valves, the combination, with the valve-stem andeccentric-rod, of the yoke R, having projection it, through which thestem passes, and the nuts T T and U, fitting on said stem on either sideof said projection, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

JAMES B. ALLFREE.

Witnesses:

M. H. Esoorr, T. R. BELL.

